Best Product Entry: Open Source Internet Of Dosimeter

[Radu Motisan] Has entered a cool project into the Best Product portion of this year’s Hackaday Prize. It’s called an Open Source IoT Dosimeter. It has a Geiger tube for detecting radiation levels along with Internet connectivity and a host of other goodies.

Dubbed the KIT1, this IoT dosimeter can be used as a portable radiation detector with its Nokia 5110 LCD as an output or a monitoring station with Ethernet. With its inbuilt speaker, it alerts users to areas with excessive radiation. KIT1 is a fully functioning system with no need for a computer to get readouts, making it very handy and easy to use. It also has room for expansion for extra sensors allowing a fully customized system. The project includes all the Gerbers and a BOM so you can send it off to a PCB fab lab of your choice, solder on a few components, and have a fully functioning IoT Dosimeter. you don’t even need the LCD or the Ethernet; you can choose which output you prefer from the two and just use that allowing for some penny-pinching.

This is a great project and who doesn’t need an IOT Dosimeter these days?

Neat project! I’m interested in the claim that “this circuit will provide excellent performance comparable to commercial detectors or better.” How does one calibrate a radiation measuring instrument? That’s the problem I always struggle with when it comes to integrating a new sensor generally.

Unrelated to calibration, In my limited experience looking at radiation, it seems like sourcing Geiger-Muller tubes is also kind of a crap shoot… are there reliable sources out there? Pointers?

Just Vandalise a Russian Lighthouse those are powered with an RTG, 2 geniuses in search of scrap metal found the bright way out on this one and threw the Strontium into the water after stealing all the Stainless and dying in such a fun way.

The irony is in this day and age that for about $80+shipping you can get a calibrated radiation source sent to your home, or if you are on some sort of list and need someone less picky you can just go to Amazon.com, no really.

They are tested using harmless radiation sources (you can buy them on ebay), As for the calibration, I’ll let Radu answer.. I know he characterizes each unit sold, and embed the values in the firmware (I own a model A since Dec 2014).

You calibrate them by measuring a source of known intensity at a fixed distance, from which you can calculate the intrinsic efficiency of the tube (how many counts it registers per radiation particle entering the detector, always less than 1).

For more sensitive detectors you need several known test sources of different types, but GM detectors are pretty crap anyway so you only really need one. You can buy the sources from a lab, but they’re kinda pricey. Or you could use something off of Ebay, again GM tubes aren’t very sensitive anyway so it doesn’t matter much.

You cannot perform callibration at home but there is conversion coefficient available for the used tube (SBM-20) to recalculate number of pulses per second (or per minute) to dose rate in microSv/h for example. But it is definitely not device for precise measurements.

You can also test the detector functionality in high radiation levels with signal generator used to work as a fake GM tube and provide appropriate high number of pulses in the circuit.

The choice of Ethernet instead of WiFi seems odd now that we have so many “Internet of crappy Things” being made now but it has Power Over Ethernet so that may be a bonus for some. As far as I know, most boundary routers/modems don’t support POE.

You can buy dirt cheap POE injectors (which are not standards abiding, but it works flawlessly in this case). As for why go for Ethernet : Reliability, price at the moment of conception, the projects is older than the Internet Of S#!T$ trend (<2014). The latest models (A3 and D) have WiFi.

Ethernet is not odd, it’s perfect for that kind of thing. In any case you have a wire to sensor, for power supply, because rechargeable battery is not an option for something, that should just fork for years without all that recharging/replacing crap. So, Ethernet with POE is the best you can think out for connecting sensors. (or you could try to develop rechargeable batteries with unlimited cycles and few orders larger capacity)

Ufortunately, there are no cheap (I mean really cheap), easy sourceable and ready-to-use Ethernet+MCU solutions like ESP8266 for WiFi.

The SBM-20 (or STS-5) appears to still be quite expensive. Ranging from 15USD to 36USD in small quantities.
This is def cheaper that $60 for some of the other tubes but wondering if a cheaper mechanism.

Also SBM-20 does not appear to detect alpha particles (only beta and gamma) which is obviously good but what about Alphas ?